fyi...Canon say's they'll replace my battery free of charge.

Clearly...they must be having a problem with their batts.

Or they are providing good customer service, or both.

Storage om Lithium batteries
 

Hi, I have read you shall not store a Lithium battery in a charged state, quite opposite compared to all other batteries I know about.

A fully charged battery inactivates slowly and it may later be difficult to get the charge out of it.

A possible cure would be to add a fairly large resistor which the battery could supply with current without dropping the voltage too much. Then wait until it is discharged and then try a normal charge - discharge cycle.

Anybody who have experience regarding this or the XL H1 Graphite battery is still too new for getting these kind of troubles?

Johan, the Li-Ion batteries age about 10%/year in average. They age a little faster if fully charged, this is why the manufacturers store them and ship them at about 40%-50% charge level, as this is optimum charge level for storage. Once they lost their capacity as they age, the loss is permanent, there is no magic tricks to make them as good as new (like many other things in life...)